Ever since he was shown at the Black Gates in the FOTR prologue, I've really wanted to see him in action. Faramir: “I do not love the bright sword for its sharpness, nor the arrow for its swiftness, nor the warrior for his glory. I love only that which they defend.”

Tolkien, in the book, suggests that Elrond remained in Rivendell when the Necromancer was driven from Southern Mirkwood; on the other hand, he didn't have a clear idea yet of the composition of the White Council, simply describing it as "a council of white wizards."

I remember a sequence, fairly early in production, that showed Gandalf and Elrond together in either Dol Guldur or the High Fells (can anyone clarify this?). So, Elrond might take part in the attack on Dol Guldur after all. If he does then he will likely function as the war-leader of the Council and command any troops that accompanied it (possibly his sons, other members of his household, a contingent of Rangers, etc.). 'There are older and fouler things than Orcs in the deep places of the world.' - Gandalf the Grey, The Fellowship of the Ring

In the Empire magazine August 2011 issue, the author of the article had written that whilst on set, both Ian McKellen and Hugo Weaving were to shoot some scenes which sees Gandalf and Elrond exploring the dungeons of Dol Guldur.

Whether this was to form part of The Desolation of Smaug sequence (before Gandalf is captured) and Elrond didn't make the cut, is uncertain.

Perhaps, they can always insert this "exploration sequence" someway or other either during or after the attack on Dol Guldur ...

It would indeed be nice to see Elrond in action, but I am not certain the armor from this photo is any indication that he'll feature in the battle at Dol Guldur.

As you recall, this is the outfit he is wearing upon his return from hunting the orc party south of Rivendell, when he surprises the company on horseback. So I dunno if we'll have the opportunity to see it again "After all, I believe that legends and myths are largely made of 'truth', and indeed present aspects of it that can only be received in this mode; and long ago certain truths and modes of this kind were discovered and must always reappear." Professor Tolkien, 1951

As long as we get to see Elrond in armor, I'm all for him appearing at Dol Guldur. "I had forgotten that. It is hard to be sure of anything among so many marvels. The world is all grown strange. Elf and Dwarf in company walk in our daily fields; and folk speak with the Lady of the Wood and yet live; and the Sword comes back to war that was broken in the long ages ere the fathers of our fathers rode into the Mark! How shall a man judge what to do in such times?"

"As he ever has judged. Good and ill have not changed since yesteryear; nor are they one thing among Elves and Dwarves and another among Men. It is a man's part to discern them, as much in the Golden Wood as in his own house."

If we ignore the fact that Tolkien had not solidified the composition of the White Council at the time he wrote The Hobbit, we could come up with one or two in-story explanations for what Gandalf said to Elrond in Rivendell:

1. Elrond remained in Rivendell in case Sauron moved against it before the Council could act. Or, perhaps he just wanted to keep his Ring far from Dol Guldur.

2. Elrond was at Dol Guldur, but he and Gandalf engaged in double-talk because of Bilbo's presence. The hobbit did not need to know that Elrond was part of the White Council. 'There are older and fouler things than Orcs in the deep places of the world.' - Gandalf the Grey, The Fellowship of the Ring

I'm pretty sure Elrond will fight at some point. Ok, I have no real proof/evidence, but the fight (Sauron - Gandalf) was even less likely to see Elrond fight after all! Bad english is bad. (English is not my native language)